The flight path of an arrow is influenced by many factors. Some factors, such as air currents, cannot be controlled by the archer. The major influences, however, on arrow trajectory are the physical actions of the archer. Accordingly, it is important for an archer to command the physically controllable factors to facilitate consistency and accuracy.
The draw and release of the bowstring play an important part in defining the flight path of the arrow. After the arrow is nocked to the bowstring, the archer pulls the bowstring to a drawn position in preparation for firing. This places the bowstring in considerable tension. The archer then releases the bowstring by relaxing his grip. The bowstring is energized and responds by advancing instantaneously from the drawn position. This firing action propels the arrow. While this technique may be mastered for consistency through repetition, it can be appreciated that slight unintended and unnoticed adjustments or twitches during the release motion can significantly alter the desired trajectory of the arrow.
Various bowstring release devices have been developed in order to normalize the release motion. The mechanics of these devices is intended to provide uniformity and consistency from use to use.
Many prior art bowstring release devices utilize a trigger mechanism that is actuated by the archer. U.S. Pat. No. 3,937,206 to Wilson discloses a bowstring release device having a pivotable trigger mechanism that initiates the bowstring release mode. A rope loop is attached to the housing of the release device and extends around the bowstring for engagement. The rope loop is hooked in a notch formed in a release wheel to hold the bowstring as it is drawn. A sear block bears against the release wheel and is held against movement by a trigger block, thus holding the release wheel in position for drawing the bowstring. When the archer pulls the trigger lever on the trigger block, the trigger block pivots to disengage from the sear block. The sear block is no longer able to hold the release wheel which rotates to allow release of the bowstring.
U.S. Pat. No. 4,860,720 to Todd discloses a bowstring release device with a pivotable trigger that operates to extend and retract a sleeve mounted on the housing. A pair of ball bearings are mounted in the housing on opposing sides of a slot that receives the bowstring. When the sleeve is in the extended position, the ball bearings are pressed firmly together and restrain the bowstring in the slot. The sleeve retracts when the trigger is pulled, allowing the ball bearings to separate and release the bowstring.
Even though the prior art designs have provided more consistency in the release of the bowstring, they still have disadvantages. More particularly, since bowstring release devices are exposed to tremendous force in restraining the bowstring in the fully drawn position, they are subject to significant wear with use over time. As a result, the trigger must be continuously adjusted in order to maintain consistent operation. In addition, component wear introduces the opportunity for jerkiness in release motion. This substantially reduces the advantage of consistent bowstring release for which the device was designed. In extreme cases, the release device may fail, creating a hazardous situation.
Accordingly, there remains a need to provide an improved bowstring release assembly that functions with precision for its intended purpose. The device should not require constant adjustment in order to maintain uniform operation. In addition, the bowstring release assembly should have a long service life. Thus, the assembly should be formed of durable components while being of simple design.